Yahoo users closed theire accounts as they fear the hack attack. US Senator Mark Warner asked  the U.S. Securities and Exchange Commission to investigate Yahoo hacking attack. 

It seems Yahoo is facing a major problem. Due to a hack attack, it has created fears among Yahoo users, thus, made them decide to close their Yahoo accounts on Sept. 23.

On Sept. 22, the tech giant, Yahoo, disclosed that hackers had stolen the encrypted passwords and even personal details of more than 500 million Yahoo accounts in 2014. After learning the announcement of Yahoo, thousands of users took to social media to express anger over the announcement, The Star reported.

As the fears continue growing because of Yahoo disclosure on hacking, US senators demanded the tech giant to give more details of who knew what and when about a huge data breach happened in 2014.

A letter to the executive officer of Yahoo, Marissa Mayer, said that six Democratic senators addressed their opinion that the hack attack that affects 500 million user accounts was "unacceptable," BBC reported. The letter came after another Democratic Senator Mark Warner asked the  U.S. Securities and Exchange Commission to investigate Yahoo on Monday, Sept. 26.

The hacking incident happened in 2014 has been reported last week. This is the reason why many users expressed their angst on social media.

According to the six senators, Patrick Leahy, Ron Wyden, Al Franken, Elizabeth Warren, Richard Blumenthal, and Edward Markey, they were disturbed why the incident only revealed after two years.  This is the reason why they said that it is acceptable.

"That means millions of Americans' data may have been compromised for two years," the senators wrote in their letter.

Yahoo agreed a deal in July for Verizon to buy its core business. At that time, the giant tech is already facing class actions lawsuits.